epiglucan and Autoimmune-Diseases

Arthritis in a genetically susceptible SKG strain of mice models a theoretical paradigm wherein autoimmune arthritis arises because of interplay between preexisting autoreactive T cells and environmental stimuli. SKG mice have a point mutation in ZAP-70 that results in attenuated TCR signaling, altered thymic selection, and spontaneous production of autoreactive T cells that cause arthritis following exposure to microbial β-glucans. In this study, we identify Nod2, an innate immune receptor, as a critical suppressor of arthritis in SKG mice. SKG mice deficient in Nod2 (Nod2

Topics: Animals; Arthritis; Autoimmune Diseases; beta-Glucans; Cells, Cultured; Cytokines; Disease Models, Animal; Humans; Immune Tolerance; Immunity, Innate; Mice; Mice, Inbred BALB C; Mice, Knockout; Mice, Mutant Strains; Mutation; Nod2 Signaling Adaptor Protein; Th17 Cells; ZAP-70 Protein-Tyrosine Kinase

Invasive pulmonary aspergillosis (IPA) is an important cause of morbidity/mortality in immunocompromised critically ill patients. New diagnostic strategies for early detection of IPA include the noninvasive biomarkers 1,3-β-d-glucan (BDG), serum, and bronchoalveolar (BAL) fluid galactomannan (GM). The aim of this study was to compare these markers for early detection of IPA in immunosuppressed critically ill patients.. Between December 2014 and December 2015, 49 immunosuppressed patients with respiratory failure were treated at our intensive care unit (ICU). We compared the BDG Fungitell assay with GM Platelia assay in serum and BAL for early detection of IPA. All tests were performed initially after admission at the ICU.. In our study with 49 patients, 13 (26%) had probable IPA. These patients had a higher Acute Physiology And Chronic Health Evaluation II score (28 vs 23, P<.001), Sequential Organ Failure Assessment score (16 vs 14, P<.001), more neutropenia (77% vs 30%, P<.001), worse Horowitz Index (99 vs 73 P<.020), a longer ICU stay (26 vs 17 days, P<.044), and a higher mortality rate (77% vs 58%, P<.001) as compared with patients without probable IPA. The used biomarker BDG presented in patients with probable IPA showed significantly higher levels as compared with patients without probable IPA (375 [103-1000 pg/mL; P<.001] vs 64 [30-105 pg/mL; P < .001]). Comparison of BDG with GM showed that positive serum GM could be detected in only 4 (30%), whereas positive BAL GM could be detected in 12 (92%; mean optical density index, 3.7) of 13 probable IPA cases. These results can be expressed as an overall sensitivity of 88% and a specificity of 82% for probable IPA using the BDG Fungitell assay, a sensitivity of 35% and a specificity of 70% using the serum GM Platelia assay, and a sensitivity of 70% and a specificity of 94% using the BAL GM Platelia assay. The negative predictive values of the used tests were 94% for the BDG Fungitell assay, 94% for the serum GM Platelia assay, and 90% for the BAL GM Platelia assay.. 1,3-β-d-Glucan may be a useful marker for patients under surveillance at risk for IPA. In critically ill patients with immunosuppression, early diagnosis of IPA may be improved by BDG as compared with serum GM. However, diagnostic performance and accuracy increase when BDG is run in parallel with GM from BAL; moreover, the association of the 2 parameters has also the advantage of detecting early and reliable IPA.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antineoplastic Agents; APACHE; Aspergillus; Autoimmune Diseases; beta-Glucans; Biomarkers; Bronchoalveolar Lavage Fluid; Critical Illness; Early Diagnosis; Female; Galactose; Graft Rejection; Humans; Immunocompromised Host; Immunosuppressive Agents; Intensive Care Units; Invasive Pulmonary Aspergillosis; Length of Stay; Male; Mannans; Middle Aged; Mortality; Neoplasms; Neutropenia; Organ Dysfunction Scores; Organ Transplantation; Respiration, Artificial; Respiratory Insufficiency; Retrospective Studies; Sensitivity and Specificity; Young Adult

The spondylarthritides (SpA), including ankylosing spondylitis (AS), psoriatic arthritis (PsA), reactive arthritis, and arthritis associated with inflammatory bowel disease, cause chronic inflammation of the large peripheral and axial joints, eyes, skin, ileum, and colon. Genetic studies reveal common candidate genes for AS, PsA, and Crohn's disease, including IL23R, IL12B, STAT3, and CARD9, all of which are associated with interleukin-23 (IL-23) signaling downstream of the dectin 1 β-glucan receptor. In autoimmune-prone SKG mice with mutated ZAP-70, which attenuates T cell receptor signaling and increases the autoreactivity of T cells in the peripheral repertoire, IL-17-dependent inflammatory arthritis developed after dectin 1-mediated fungal infection. This study was undertaken to determine whether SKG mice injected with 1,3-β-glucan (curdlan) develop evidence of SpA, and the relationship of innate and adaptive autoimmunity to this process.. SKG mice and control BALB/c mice were injected once with curdlan or mannan. Arthritis was scored weekly, and organs were assessed for pathologic features. Anti-IL-23 monoclonal antibodies were injected into curdlan-treated SKG mice. CD4+ T cells were transferred from curdlan-treated mice to SCID mice, and sera were analyzed for autoantibodies.. After systemic injection of curdlan, SKG mice developed enthesitis, wrist, ankle, and sacroiliac joint arthritis, dactylitis, plantar fasciitis, vertebral inflammation, ileitis resembling Crohn's disease, and unilateral uveitis. Mannan triggered spondylitis and arthritis. Arthritis and spondylitis were T cell- and IL-23-dependent and were transferable to SCID recipients with CD4+ T cells. SpA was associated with collagen- and proteoglycan-specific autoantibodies.. Our findings indicate that the SKG ZAP-70W163C mutation predisposes BALB/c mice to SpA, resulting from innate and adaptive autoimmunity, after systemic β-glucan or mannan exposure.

Topics: Animals; Arthritis, Experimental; Arthritis, Rheumatoid; Autoantibodies; Autoimmune Diseases; Autoimmunity; beta-Glucans; Ileitis; Interleukin-17; Joints; Mice; Spondylarthritis; T-Lymphocytes

SKG mice are a recently established experimental model for rheumatoid arthritis (RA). Although they spontaneously develop chronic autoimmune arthritis under conventional conditions, SKG mice failed to develop chronic arthritis in a strictly controlled specific pathogen-free (SPF) environment. Beta-glucan (BG) from Laminaria digitata, laminarin (LAM), induced arthritis under SPF conditions, thus BG would be a pathogenic factor for arthritis in SKG mice. Therefore, we prepared BG from Candida albicans, a pathogenic fungus and investigated whether BG from C. albicans induced arthritis in SKG mice under SPF conditions. SKG mice were injected intraperitoneally with particulate BG (oxidative-Candida albicans (OX-CA)), soluble BG (Candida soluble beta-glucan (CSBG)) from C. albicans and LAM as a positive control. In addition, schizophyllan (SPG) from Schizophyllum commune or Mycobacterium whole cells were injected into SKG mice to induce arthritis. Mice injected with OX-CA, CSBG and SPG had more severe arthritis than with LAM, and whole Mycobacterium cells. IL-6 concentration in sera from SKG mice injected with OX-CA or CSBG was high, whereas not detected in sera from mice treated with LAM. In histological analysis, infiltration of inflammatory cells was observed in SKG mice injected with BG. These results suggest that fungal infection may be a factor to induce and exacerbate autoimmune diseases such as RA.

Topics: Adjuvants, Immunologic; Animals; Arthritis; Autoimmune Diseases; beta-Glucans; Candida albicans; Cell Wall; Female; Interleukin-6; Male; Mice; Mice, Inbred Strains; Mycobacterium tuberculosis; Sizofiran

Collagen-induced arthritis (CIA) is an experimental model of rheumatoid arthritis (RA) used for studying the clinical, immunological and genetic factors of the disease. Many studies of genetic susceptibility to CIA have been performed, usually with two strains of mice, DBA/1 and B10.RIII, since they are highly susceptible to CIA. Furthermore, F1 hybrid mice of susceptible and resistant strains reportedly develop arthritis. Recently, we reported that particles of beta-glucan, OX-CA, prepared from Candida albicans by NaClO-oxidation, acted as an adjuvant for CIA. Although, there have been many studies about the relationship between antigen and the major histocompatibility complex (MHC) in F1 hybrid mice, little is known argument about susceptibility to adjuvants. Therefore, we checked the susceptibility of F1 hybrids to CIA using OX-CA as an adjuvant. BALB/c and DBA/1 were mated to generate F1 hybrids which were then immunized with type II collagen (CII) plus Freund's complete adjuvant (FCA) or OX-CA. The results showed that F1 hybrids injected with CII plus FCA developed severe arthritis at an incidence ratio 80%, versus only 20% in mice injected with CII plus OX-CA. Furthermore, levels of anti-CII antibody, especially of the IgG2a subclass, in sera from mice treated with CII plus OX-CA were significantly low. Susceptibility to CIA might depend on not only MHC but also the adjuvant used for immunoactivation.

Topics: Adjuvants, Immunologic; Animals; Antibody Formation; Arthritis, Experimental; Autoimmune Diseases; beta-Glucans; Collagen Type II; Freund's Adjuvant; Genetic Predisposition to Disease; Male; Mice; Mice, Inbred Strains; Species Specificity

Collagen-induced arthritis (CIA) is an experimental model of rheumatoid arthritis (RA) and has aided research into the pathogenesis of inflammatory joint disease. Typically, Type II collagen (CII) emulsified with Freund's complete adjuvant (FCA) is injected into DBA/1 mice. After a booster injection, the mice develop inflammation of the paws. But the fact that the immunization of CII alone does not induce arthritis suggests that activation of the immune system by an adjuvant is necessary for induction of the arthritis. In the present study, we investigated the ability of beta-glucans derived from Candida albicans to act as an adjuvant to induce autoimmune arthritis. DBA/1 mice were injected with CII emulsified with FCA or particulate beta-glucan, OX-CA, on day 0 and given a booster at day 21. Mice immunized with CII plus OX-CA developed arthritis at around 7-10 days after the booster injection. Similarly, mice administered CII emulsified with FCA developed arthritis with the same time course. The mice immunized with CII and OX-CA had a more severe arthritis than those immunized with CII and FCA. Histological changes and production of anti-CII antibody were observed regardless of the type of injection. In addition, components of C. albicans were also tested for their ability to induce arthritis as an adjuvant. The results showed that CSBG, which is a soluble beta-glucan, acted as an adjuvant for CIA but CAWS, which is a mannoprotein-beta-glucan complex, did not. In conclusion, beta-glucan derived from C. albicans acted as an adjuvant and the injection with CII resulted in arthritis with the production of anti-CII autoantibody. The results strongly suggested that fungal metabolites such as beta-glucans have the capacity to induce and exacerbate autoimmune diseases such as RA.

Topics: Adjuvants, Immunologic; Animals; Arthritis, Experimental; Autoantibodies; Autoimmune Diseases; beta-Glucans; Candida albicans; Cell Wall; Collagen Type II; Injections, Subcutaneous; Male; Mice; Mice, Inbred BALB C; Mice, Inbred C3H; Mice, Inbred C57BL; Mice, Inbred DBA